The cultivation of plant species sensitive to cold weather entails the use of methods designed to preserve the productive capabilities of the plants. In this scope are included plantations, such as vineyards and the like, practised in countries with cold winters or in places at high elevations.
The method provides for the growth of one or more branches that are allowed to grow either with the main trunk or as main branches on their own in the absence of a main trunk; in cold periods said branches are buried so as to be protected from freezing weather in order that they can eventually be ready to take the place of said main trunk if the latter is damaged by bad weather conditions, or else to sprout anew in the warm season in the case in which they are all main branches. This method can be used for a period that generally extends from one to five years, depending on the plant species, that is, until the hard woody consistency of the branches makes them susceptible to be broken during the bending operations.
In current practices, during the warm months, the branches are fastened in similar manner as the main trunk to support structures consisting of vertical posts that support horizontal wires. As the cold season approaches, the branches are released from the horizontal carrying wires or from the support stakes, they are placed on the ground so as to lie as much as possible parallel to the direction of the row of vines, and are covered with soil by the action of a plough drawn by a tractor. The operation with the plough, when carrying out the procedure according to the prior art method, must necessarily be performed on both sides of the row of plants to guarantee a suitable covering of said branches, and may generally require the work of operators to hold the branches being covered in a fixed position with the help of metal forks inserted into the ground so as to straddle the branches themselves.
At the end of the cold season, the branches must be returned to their initial position and secured to the horizontal carrying wire through the possible help of the current support stakes to which the branches are fastened.
The restoration process, according to the prior art, requires the removal of the soil that was previously piled up, through the use of a plough that returns the soil into the open furrows during the burying step, and the subsequent passage with blowing means or manual implements to remove the part of the soil nearest to the branches which, to protect the branches, cannot be removed with the plough.
The procedure is completed manually with the removal of the remaining soil, the metal forks, and by securing the branches to a horizontal carrying wire by tying them to the relative support stakes.